You might feel like you have sand in your eyes, or they might burn or itch. You might be sensitive to light, have blurry vision, or, in some cases, your eyes might water. And you may have a tough time wearing contact lenses. These symptoms are signs of dry eyes.

Your Eyes Need Moisture

Moisture helps your eyes work the way they’re supposed to and keeps them comfortable. Your body normally makes moisture for your eyes, but when you can’t — or it’s not good quality — that can make your eyes hurt and affect your eyesight.

What Your Tears Do

They soothe the surface of your eyes and protect them from things like debris and infection. Each time you blink, they go over your eyes, then drain into the inner corners of your eyelids to the back of your nose. If you don’t make enough good-quality tears, your eyes can be dry and irritated.

Dry Eye Syndrome

The most common kind of dry eye happens because your body doesn’t make enough tears. This is called dry eye syndrome, or keratoconjunctivitis sicca (KCS). Many things can cause it. Depending on what that is, it can go away on its own or last a long time.

Possible Cause: Age

The glands that make tears don’t work as well as you age, so you don’t make as many. Also, your eyelids begin to sag, and that can break the seal against your eyeball that helps keep in moisture.

Possible Cause: Certain Illnesses

Autoimmune diseases — when your immune system attacks parts of your body — can affect your body’s ability to make tears and cause dry eyes. Examples include lupus and rheumatoid arthritis, as well as Sjogren’s syndrome, which attacks saliva and tear glands.

Possible Cause: Eye Surgery

Dry eyes can be a side effect of cataract surgery and LASIK or PRK surgery, which correct vision problems. The nerves that help you make tears can be damaged during these procedures. Talk with your doctor about eyedrops and other things that can help. For most people, it gets better as your eyes recover.

Evaporative Dry Eye

If your tears don’t have enough oil in them, they can evaporate (get absorbed into the air) before your eyes get enough moisture. This often happens when the glands that give your tears their oily texture are blocked. Also called Meibomian gland dysfunction, it’s treated with warm washcloths and lid scrubs that clear away the dead skin, oil, and bacteria that can build up and plug the glands.

Tear Duct Infection

Also called dacryocystitis, this happens when a tear duct — the small tube that runs down the length of your nose and connects to your eyelid — gets blocked and bacteria get in the area. It’s most common in infants, but it can happen at any age. Symptoms include pain, redness, swelling, too many tears, discharge from your eye, and fever. Antibiotics are the most common treatment, but some people need minor surgery to clear it up.

Medications

If you have symptoms of dry eyes and take medication, read the label. Some drugs, such as antihistamines, beta-blockers, and some antidepressants, can affect your tears and dry out your eyes. Talk with your doctor to find out if this is a problem for you.

What Can Make It Worse: Low Humidity

If there’s not a lot of moisture in the air — in a heated or air-conditioned room or in an airplane, for example — dry eyes can get even more irritated. And a lot of wind can do it, too (that includes riding a bike without protective eyewear).

What Can Make It Worse: Too Much Screen Time

Looking at a computer or phone screen for long periods of time can cause problems because you’re less likely to blink and get moisture over your eyes.

What Can Make It Worse: Contact Lenses

They sit inside the tear film, so when that’s dry, it can make it difficult and uncomfortable — even impossible — to wear them. Talk to your doctor if you’re having trouble with your contacts: It may help to change solutions or use lenses made from a different material.

What You Can Do: Artificial Tears

These aren’t the kind your toddler uses when he’s trying to get away with something. These tears come from the drugstore as drops or ointment. Some have a chemical that can stop working if you use them too long, but not all have that. Talk to your doctor about what may work for you.

What You Can Do: Change Your Diet

Among other health benefits, omega-3 fatty acids also may help keep your eyes moist. The best place to get them is from fish like salmon, sardines, and mackerel. If you don’t like fish, you can take a supplement instead. 

Prevention

If your eyes are dry, it’s a good idea to stay away from some things that can irritate them, like hair dryers, air conditioning, wind, smoke, and some chemicals. Use a humidifier, and take regular breaks if you spend long hours at a computer. During sports or outdoor activities, use swim or ski goggles or other protective eyewear that helps you keep moisture around your eyes.

When to Call Your Doctor

If dry eyes are new to you and you’ve had them for more than a few days, talk with your doctor. It’s also a good idea to check with him before you use over-the-counter artificial tears. In most cases, dry eyes are more of an annoyance than a health danger, but it’s always best to be sure.

*WebMD